Push fastener



FIG. 1 is a perspective view of a push fastener showing my new design;

FIG. 2 is a front elevational view thereof, the rear being identical;

FIG. 3 is a right side elevational view thereof, the left side being identical;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a push fastener, as shown and described. 